What is Underdosing? (Peptide Glossary)

Underdosing - putting 3mg in a vial labeled 5mg - is the most prevalent form of vendor fraud in the research peptide market, because it is nearly undetectable without laboratory testing. Purity testing (HPLC) does not catch it: a vial can be 99% pure and still contain half the labeled amount. Quantity requires quantitative analysis or simple gravimetric checking.

The economics are straightforward. Peptide raw material is the dominant cost, so shaving 20-40% off fill quantity flows directly to margin. Community-funded testing programs have repeatedly caught vendors underdosing - sometimes by more than half - while their COAs showed perfect purity. This is why price shopping without quantity verification is dangerous: the cheapest vendor may simply be selling less peptide per vial.

Defenses: favor vendors with third-party quantitative testing or community testing participation, be suspicious of prices far below the market floor for complex compounds, and note that vendor review communities track underdosing reports closely. Our sentiment pipeline specifically watches for underdosing complaints in Reddit and forum mentions.